<font color="red"> PJ,
I think that you have the same style PT-425 that I do, (2/2004).
A couple months ago it got cranky (or is it uncranky?) about starting and required a jump from the 1000 AH battery on my little Power King.
After doing some measuring, it appears that with a little grinding my usual battery cure of installing the largest one that I can find, 1000 AH, would work for the PT-425 as well!! However, the PT's reluctance went away, so I haven't upgraded yet.
Over the years I have replaced OEM batteries in 5 cars, 3 SUVs, and my CUT with 1000 AH batteries and never had another battery related problem! Big engine, small engine, very hot, bitter cold, parked inside, parked outside, started often, started seldom - doesn't matter! Just hit the key and away we go!!
They cost a little more, but come with long warranties, and are so RELIABLE!!
If you want to use the "Magnetic light, air pump, 12 drill. 12v impact wrench. all the 12v goodies." as J.J. suggested, you won't have to let the engine run or have a dead battery within 10 minutes!! Great for providing jump starts anywhere the PT can go!
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